1 files changed, 447 insertions, 266 deletions

diff --git a/fs/cifs/transport.c b/fs/cifs/transport.c
index 0cc9584f588..18cd5650a5f 100644
--- a/fs/cifs/transport.c
+++ b/fs/cifs/transport.c
@@ -27,6 +27,8 @@
 #include <linux/net.h>
 #include <linux/delay.h>
 #include <linux/freezer.h>
+#include <linux/tcp.h>
+#include <linux/highmem.h>
 #include <asm/uaccess.h>
 #include <asm/processor.h>
 #include <linux/mempool.h>
@@ -35,10 +37,8 @@
 #include "cifsproto.h"
 #include "cifs_debug.h"
 
-extern mempool_t *cifs_mid_poolp;
-
-static void
-wake_up_task(struct mid_q_entry *mid)
+void
+cifs_wake_up_task(struct mid_q_entry *mid)
 {
 	wake_up_process(mid->callback_data);
 }
@@ -49,7 +49,7 @@ AllocMidQEntry(const struct smb_hdr *smb_buffer, struct TCP_Server_Info *server)
 	struct mid_q_entry *temp;
 
 	if (server == NULL) {
-		cERROR(1, "Null TCP session in AllocMidQEntry");
+		cifs_dbg(VFS, "Null TCP session in AllocMidQEntry\n");
 		return NULL;
 	}
 
@@ -58,24 +58,25 @@ AllocMidQEntry(const struct smb_hdr *smb_buffer, struct TCP_Server_Info *server)
 		return temp;
 	else {
 		memset(temp, 0, sizeof(struct mid_q_entry));
-		temp->mid = smb_buffer->Mid;	/* always LE */
+		temp->mid = get_mid(smb_buffer);
 		temp->pid = current->pid;
-		temp->command = smb_buffer->Command;
-		cFYI(1, "For smb_command %d", temp->command);
+		temp->command = cpu_to_le16(smb_buffer->Command);
+		cifs_dbg(FYI, "For smb_command %d\n", smb_buffer->Command);
 	/*	do_gettimeofday(&temp->when_sent);*/ /* easier to use jiffies */
 		/* when mid allocated can be before when sent */
 		temp->when_alloc = jiffies;
+		temp->server = server;
 
 		/*
 		 * The default is for the mid to be synchronous, so the
 		 * default callback just wakes up the current task.
 		 */
-		temp->callback = wake_up_task;
+		temp->callback = cifs_wake_up_task;
 		temp->callback_data = current;
 	}
 
 	atomic_inc(&midCount);
-	temp->midState = MID_REQUEST_ALLOCATED;
+	temp->mid_state = MID_REQUEST_ALLOCATED;
 	return temp;
 }
 
@@ -83,11 +84,12 @@ void
 DeleteMidQEntry(struct mid_q_entry *midEntry)
 {
 #ifdef CONFIG_CIFS_STATS2
+	__le16 command = midEntry->server->vals->lock_cmd;
 	unsigned long now;
 #endif
-	midEntry->midState = MID_FREE;
+	midEntry->mid_state = MID_FREE;
 	atomic_dec(&midCount);
-	if (midEntry->largeBuf)
+	if (midEntry->large_buf)
 		cifs_buf_release(midEntry->resp_buf);
 	else
 		cifs_small_buf_release(midEntry->resp_buf);
@@ -96,9 +98,8 @@ DeleteMidQEntry(struct mid_q_entry *midEntry)
 	/* commands taking longer than one second are indications that
 	   something is wrong, unless it is quite a slow link or server */
 	if ((now - midEntry->when_alloc) > HZ) {
-		if ((cifsFYI & CIFS_TIMER) &&
-		   (midEntry->command != SMB_COM_LOCKING_ANDX)) {
-			printk(KERN_DEBUG " CIFS slow rsp: cmd %d mid %d",
+		if ((cifsFYI & CIFS_TIMER) && (midEntry->command != command)) {
+			printk(KERN_DEBUG " CIFS slow rsp: cmd %d mid %llu",
 			       midEntry->command, midEntry->mid);
 			printk(" A: 0x%lx S: 0x%lx R: 0x%lx\n",
 			       now - midEntry->when_alloc,
@@ -110,8 +111,8 @@ DeleteMidQEntry(struct mid_q_entry *midEntry)
 	mempool_free(midEntry, cifs_mid_poolp);
 }
 
-static void
-delete_mid(struct mid_q_entry *mid)
+void
+cifs_delete_mid(struct mid_q_entry *mid)
 {
 	spin_lock(&GlobalMid_Lock);
 	list_del(&mid->qhead);
@@ -120,21 +121,28 @@ delete_mid(struct mid_q_entry *mid)
 	DeleteMidQEntry(mid);
 }
 
+/*
+ * smb_send_kvec - send an array of kvecs to the server
+ * @server:	Server to send the data to
+ * @iov:	Pointer to array of kvecs
+ * @n_vec:	length of kvec array
+ * @sent:	amount of data sent on socket is stored here
+ *
+ * Our basic "send data to server" function. Should be called with srv_mutex
+ * held. The caller is responsible for handling the results.
+ */
 static int
-smb_sendv(struct TCP_Server_Info *server, struct kvec *iov, int n_vec)
+smb_send_kvec(struct TCP_Server_Info *server, struct kvec *iov, size_t n_vec,
+		size_t *sent)
 {
 	int rc = 0;
 	int i = 0;
 	struct msghdr smb_msg;
-	struct smb_hdr *smb_buffer = iov[0].iov_base;
-	unsigned int len = iov[0].iov_len;
-	unsigned int total_len;
-	int first_vec = 0;
-	unsigned int smb_buf_length = be32_to_cpu(smb_buffer->smb_buf_length);
+	unsigned int remaining;
+	size_t first_vec = 0;
 	struct socket *ssocket = server->ssocket;
 
-	if (ssocket == NULL)
-		return -ENOTSOCK; /* BB eventually add reconnect code here */
+	*sent = 0;
 
 	smb_msg.msg_name = (struct sockaddr *) &server->dstaddr;
 	smb_msg.msg_namelen = sizeof(struct sockaddr);
@@ -145,64 +153,70 @@ smb_sendv(struct TCP_Server_Info *server, struct kvec *iov, int n_vec)
 	else
 		smb_msg.msg_flags = MSG_NOSIGNAL;
 
-	total_len = 0;
+	remaining = 0;
 	for (i = 0; i < n_vec; i++)
-		total_len += iov[i].iov_len;
-
-	cFYI(1, "Sending smb:  total_len %d", total_len);
-	dump_smb(smb_buffer, len);
+		remaining += iov[i].iov_len;
 
 	i = 0;
-	while (total_len) {
+	while (remaining) {
+		/*
+		 * If blocking send, we try 3 times, since each can block
+		 * for 5 seconds. For nonblocking  we have to try more
+		 * but wait increasing amounts of time allowing time for
+		 * socket to clear.  The overall time we wait in either
+		 * case to send on the socket is about 15 seconds.
+		 * Similarly we wait for 15 seconds for a response from
+		 * the server in SendReceive[2] for the server to send
+		 * a response back for most types of requests (except
+		 * SMB Write past end of file which can be slow, and
+		 * blocking lock operations). NFS waits slightly longer
+		 * than CIFS, but this can make it take longer for
+		 * nonresponsive servers to be detected and 15 seconds
+		 * is more than enough time for modern networks to
+		 * send a packet.  In most cases if we fail to send
+		 * after the retries we will kill the socket and
+		 * reconnect which may clear the network problem.
+		 */
 		rc = kernel_sendmsg(ssocket, &smb_msg, &iov[first_vec],
-				    n_vec - first_vec, total_len);
-		if ((rc == -ENOSPC) || (rc == -EAGAIN)) {
+				    n_vec - first_vec, remaining);
+		if (rc == -EAGAIN) {
 			i++;
-			/* if blocking send we try 3 times, since each can block
-			   for 5 seconds. For nonblocking  we have to try more
-			   but wait increasing amounts of time allowing time for
-			   socket to clear.  The overall time we wait in either
-			   case to send on the socket is about 15 seconds.
-			   Similarly we wait for 15 seconds for
-			   a response from the server in SendReceive[2]
-			   for the server to send a response back for
-			   most types of requests (except SMB Write
-			   past end of file which can be slow, and
-			   blocking lock operations). NFS waits slightly longer
-			   than CIFS, but this can make it take longer for
-			   nonresponsive servers to be detected and 15 seconds
-			   is more than enough time for modern networks to
-			   send a packet.  In most cases if we fail to send
-			   after the retries we will kill the socket and
-			   reconnect which may clear the network problem.
-			*/
-			if ((i >= 14) || (!server->noblocksnd && (i > 2))) {
-				cERROR(1, "sends on sock %p stuck for 15 seconds",
-				    ssocket);
+			if (i >= 14 || (!server->noblocksnd && (i > 2))) {
+				cifs_dbg(VFS, "sends on sock %p stuck for 15 seconds\n",
+					 ssocket);
 				rc = -EAGAIN;
 				break;
 			}
 			msleep(1 << i);
 			continue;
 		}
+
 		if (rc < 0)
 			break;
 
-		if (rc == total_len) {
-			total_len = 0;
+		/* send was at least partially successful */
+		*sent += rc;
+
+		if (rc == remaining) {
+			remaining = 0;
 			break;
-		} else if (rc > total_len) {
-			cERROR(1, "sent %d requested %d", rc, total_len);
+		}
+
+		if (rc > remaining) {
+			cifs_dbg(VFS, "sent %d requested %d\n", rc, remaining);
 			break;
 		}
+
 		if (rc == 0) {
 			/* should never happen, letting socket clear before
 			   retrying is our only obvious option here */
-			cERROR(1, "tcp sent no data");
+			cifs_dbg(VFS, "tcp sent no data\n");
 			msleep(500);
 			continue;
 		}
-		total_len -= rc;
+
+		remaining -= rc;
+
 		/* the line below resets i */
 		for (i = first_vec; i < n_vec; i++) {
 			if (iov[i].iov_len) {
@@ -217,31 +231,150 @@ smb_sendv(struct TCP_Server_Info *server, struct kvec *iov, int n_vec)
 				}
 			}
 		}
+
 		i = 0; /* in case we get ENOSPC on the next send */
+		rc = 0;
+	}
+	return rc;
+}
+
+/**
+ * rqst_page_to_kvec - Turn a slot in the smb_rqst page array into a kvec
+ * @rqst: pointer to smb_rqst
+ * @idx: index into the array of the page
+ * @iov: pointer to struct kvec that will hold the result
+ *
+ * Helper function to convert a slot in the rqst->rq_pages array into a kvec.
+ * The page will be kmapped and the address placed into iov_base. The length
+ * will then be adjusted according to the ptailoff.
+ */
+void
+cifs_rqst_page_to_kvec(struct smb_rqst *rqst, unsigned int idx,
+			struct kvec *iov)
+{
+	/*
+	 * FIXME: We could avoid this kmap altogether if we used
+	 * kernel_sendpage instead of kernel_sendmsg. That will only
+	 * work if signing is disabled though as sendpage inlines the
+	 * page directly into the fraglist. If userspace modifies the
+	 * page after we calculate the signature, then the server will
+	 * reject it and may break the connection. kernel_sendmsg does
+	 * an extra copy of the data and avoids that issue.
+	 */
+	iov->iov_base = kmap(rqst->rq_pages[idx]);
+
+	/* if last page, don't send beyond this offset into page */
+	if (idx == (rqst->rq_npages - 1))
+		iov->iov_len = rqst->rq_tailsz;
+	else
+		iov->iov_len = rqst->rq_pagesz;
+}
+
+static unsigned long
+rqst_len(struct smb_rqst *rqst)
+{
+	unsigned int i;
+	struct kvec *iov = rqst->rq_iov;
+	unsigned long buflen = 0;
+
+	/* total up iov array first */
+	for (i = 0; i < rqst->rq_nvec; i++)
+		buflen += iov[i].iov_len;
+
+	/* add in the page array if there is one */
+	if (rqst->rq_npages) {
+		buflen += rqst->rq_pagesz * (rqst->rq_npages - 1);
+		buflen += rqst->rq_tailsz;
+	}
+
+	return buflen;
+}
+
+static int
+smb_send_rqst(struct TCP_Server_Info *server, struct smb_rqst *rqst)
+{
+	int rc;
+	struct kvec *iov = rqst->rq_iov;
+	int n_vec = rqst->rq_nvec;
+	unsigned int smb_buf_length = get_rfc1002_length(iov[0].iov_base);
+	unsigned long send_length;
+	unsigned int i;
+	size_t total_len = 0, sent;
+	struct socket *ssocket = server->ssocket;
+	int val = 1;
+
+	if (ssocket == NULL)
+		return -ENOTSOCK;
+
+	/* sanity check send length */
+	send_length = rqst_len(rqst);
+	if (send_length != smb_buf_length + 4) {
+		WARN(1, "Send length mismatch(send_length=%lu smb_buf_length=%u)\n",
+			send_length, smb_buf_length);
+		return -EIO;
+	}
+
+	cifs_dbg(FYI, "Sending smb: smb_len=%u\n", smb_buf_length);
+	dump_smb(iov[0].iov_base, iov[0].iov_len);
+
+	/* cork the socket */
+	kernel_setsockopt(ssocket, SOL_TCP, TCP_CORK,
+				(char *)&val, sizeof(val));
+
+	rc = smb_send_kvec(server, iov, n_vec, &sent);
+	if (rc < 0)
+		goto uncork;
+
+	total_len += sent;
+
+	/* now walk the page array and send each page in it */
+	for (i = 0; i < rqst->rq_npages; i++) {
+		struct kvec p_iov;
+
+		cifs_rqst_page_to_kvec(rqst, i, &p_iov);
+		rc = smb_send_kvec(server, &p_iov, 1, &sent);
+		kunmap(rqst->rq_pages[i]);
+		if (rc < 0)
+			break;
+
+		total_len += sent;
 	}
 
+uncork:
+	/* uncork it */
+	val = 0;
+	kernel_setsockopt(ssocket, SOL_TCP, TCP_CORK,
+				(char *)&val, sizeof(val));
+
 	if ((total_len > 0) && (total_len != smb_buf_length + 4)) {
-		cFYI(1, "partial send (%d remaining), terminating session",
-			total_len);
-		/* If we have only sent part of an SMB then the next SMB
-		   could be taken as the remainder of this one.  We need
-		   to kill the socket so the server throws away the partial
-		   SMB */
+		cifs_dbg(FYI, "partial send (wanted=%u sent=%zu): terminating session\n",
+			 smb_buf_length + 4, total_len);
+		/*
+		 * If we have only sent part of an SMB then the next SMB could
+		 * be taken as the remainder of this one. We need to kill the
+		 * socket so the server throws away the partial SMB
+		 */
 		server->tcpStatus = CifsNeedReconnect;
 	}
 
 	if (rc < 0 && rc != -EINTR)
-		cERROR(1, "Error %d sending data on socket to server", rc);
+		cifs_dbg(VFS, "Error %d sending data on socket to server\n",
+			 rc);
 	else
 		rc = 0;
 
-	/* Don't want to modify the buffer as a
-	   side effect of this call. */
-	smb_buffer->smb_buf_length = cpu_to_be32(smb_buf_length);
-
 	return rc;
 }
 
+static int
+smb_sendv(struct TCP_Server_Info *server, struct kvec *iov, int n_vec)
+{
+	struct smb_rqst rqst = { .rq_iov = iov,
+				 .rq_nvec = n_vec };
+
+	return smb_send_rqst(server, &rqst);
+}
+
 int
 smb_send(struct TCP_Server_Info *server, struct smb_hdr *smb_buffer,
 	 unsigned int smb_buf_length)
@@ -254,44 +387,67 @@ smb_send(struct TCP_Server_Info *server, struct smb_hdr *smb_buffer,
 	return smb_sendv(server, &iov, 1);
 }
 
-static int wait_for_free_request(struct TCP_Server_Info *server,
-				 const int long_op)
+static int
+wait_for_free_credits(struct TCP_Server_Info *server, const int timeout,
+		      int *credits)
 {
-	if (long_op == CIFS_ASYNC_OP) {
+	int rc;
+
+	spin_lock(&server->req_lock);
+	if (timeout == CIFS_ASYNC_OP) {
 		/* oplock breaks must not be held up */
-		atomic_inc(&server->inFlight);
+		server->in_flight++;
+		*credits -= 1;
+		spin_unlock(&server->req_lock);
 		return 0;
 	}
 
-	spin_lock(&GlobalMid_Lock);
 	while (1) {
-		if (atomic_read(&server->inFlight) >= cifs_max_pending) {
-			spin_unlock(&GlobalMid_Lock);
+		if (*credits <= 0) {
+			spin_unlock(&server->req_lock);
 			cifs_num_waiters_inc(server);
-			wait_event(server->request_q,
-				   atomic_read(&server->inFlight)
-				     < cifs_max_pending);
+			rc = wait_event_killable(server->request_q,
+						 has_credits(server, credits));
 			cifs_num_waiters_dec(server);
-			spin_lock(&GlobalMid_Lock);
+			if (rc)
+				return rc;
+			spin_lock(&server->req_lock);
 		} else {
 			if (server->tcpStatus == CifsExiting) {
-				spin_unlock(&GlobalMid_Lock);
+				spin_unlock(&server->req_lock);
 				return -ENOENT;
 			}
 
-			/* can not count locking commands against total
-			   as they are allowed to block on server */
+			/*
+			 * Can not count locking commands against total
+			 * as they are allowed to block on server.
+			 */
 
 			/* update # of requests on the wire to server */
-			if (long_op != CIFS_BLOCKING_OP)
-				atomic_inc(&server->inFlight);
-			spin_unlock(&GlobalMid_Lock);
+			if (timeout != CIFS_BLOCKING_OP) {
+				*credits -= 1;
+				server->in_flight++;
+			}
+			spin_unlock(&server->req_lock);
 			break;
 		}
 	}
 	return 0;
 }
 
+static int
+wait_for_free_request(struct TCP_Server_Info *server, const int timeout,
+		      const int optype)
+{
+	int *val;
+
+	val = server->ops->get_credits_field(server, optype);
+	/* Since an echo is already inflight, no need to wait to send another */
+	if (*val <= 0 && optype == CIFS_ECHO_OP)
+		return -EAGAIN;
+	return wait_for_free_credits(server, timeout, val);
+}
+
 static int allocate_mid(struct cifs_ses *ses, struct smb_hdr *in_buf,
 			struct mid_q_entry **ppmidQ)
 {
@@ -300,17 +456,24 @@ static int allocate_mid(struct cifs_ses *ses, struct smb_hdr *in_buf,
 	}
 
 	if (ses->server->tcpStatus == CifsNeedReconnect) {
-		cFYI(1, "tcp session dead - return to caller to retry");
+		cifs_dbg(FYI, "tcp session dead - return to caller to retry\n");
 		return -EAGAIN;
 	}
 
-	if (ses->status != CifsGood) {
-		/* check if SMB session is bad because we are setting it up */
+	if (ses->status == CifsNew) {
 		if ((in_buf->Command != SMB_COM_SESSION_SETUP_ANDX) &&
 			(in_buf->Command != SMB_COM_NEGOTIATE))
 			return -EAGAIN;
 		/* else ok - we are setting up session */
 	}
+
+	if (ses->status == CifsExiting) {
+		/* check if SMB session is bad because we are setting it up */
+		if (in_buf->Command != SMB_COM_LOGOFF_ANDX)
+			return -EAGAIN;
+		/* else ok - we are shutting down session */
+	}
+
 	*ppmidQ = AllocMidQEntry(in_buf, ses->server);
 	if (*ppmidQ == NULL)
 		return -ENOMEM;
@@ -325,74 +488,91 @@ wait_for_response(struct TCP_Server_Info *server, struct mid_q_entry *midQ)
 {
 	int error;
 
-	error = wait_event_freezekillable(server->response_q,
-				    midQ->midState != MID_REQUEST_SUBMITTED);
+	error = wait_event_freezekillable_unsafe(server->response_q,
+				    midQ->mid_state != MID_REQUEST_SUBMITTED);
 	if (error < 0)
 		return -ERESTARTSYS;
 
 	return 0;
 }
 
+struct mid_q_entry *
+cifs_setup_async_request(struct TCP_Server_Info *server, struct smb_rqst *rqst)
+{
+	int rc;
+	struct smb_hdr *hdr = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
+	struct mid_q_entry *mid;
+
+	/* enable signing if server requires it */
+	if (server->sign)
+		hdr->Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
+
+	mid = AllocMidQEntry(hdr, server);
+	if (mid == NULL)
+		return ERR_PTR(-ENOMEM);
+
+	rc = cifs_sign_rqst(rqst, server, &mid->sequence_number);
+	if (rc) {
+		DeleteMidQEntry(mid);
+		return ERR_PTR(rc);
+	}
+
+	return mid;
+}
 
 /*
  * Send a SMB request and set the callback function in the mid to handle
  * the result. Caller is responsible for dealing with timeouts.
  */
 int
-cifs_call_async(struct TCP_Server_Info *server, struct kvec *iov,
-		unsigned int nvec, mid_receive_t *receive,
-		mid_callback_t *callback, void *cbdata, bool ignore_pend)
+cifs_call_async(struct TCP_Server_Info *server, struct smb_rqst *rqst,
+		mid_receive_t *receive, mid_callback_t *callback,
+		void *cbdata, const int flags)
 {
-	int rc;
+	int rc, timeout, optype;
 	struct mid_q_entry *mid;
-	struct smb_hdr *hdr = (struct smb_hdr *)iov[0].iov_base;
 
-	rc = wait_for_free_request(server, ignore_pend ? CIFS_ASYNC_OP : 0);
+	timeout = flags & CIFS_TIMEOUT_MASK;
+	optype = flags & CIFS_OP_MASK;
+
+	rc = wait_for_free_request(server, timeout, optype);
 	if (rc)
 		return rc;
 
-	/* enable signing if server requires it */
-	if (server->sec_mode & (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED))
-		hdr->Flags2 |= SMBFLG2_SECURITY_SIGNATURE;
-
 	mutex_lock(&server->srv_mutex);
-	mid = AllocMidQEntry(hdr, server);
-	if (mid == NULL) {
+	mid = server->ops->setup_async_request(server, rqst);
+	if (IS_ERR(mid)) {
 		mutex_unlock(&server->srv_mutex);
-		atomic_dec(&server->inFlight);
+		add_credits(server, 1, optype);
 		wake_up(&server->request_q);
-		return -ENOMEM;
+		return PTR_ERR(mid);
 	}
 
+	mid->receive = receive;
+	mid->callback = callback;
+	mid->callback_data = cbdata;
+	mid->mid_state = MID_REQUEST_SUBMITTED;
+
 	/* put it on the pending_mid_q */
 	spin_lock(&GlobalMid_Lock);
 	list_add_tail(&mid->qhead, &server->pending_mid_q);
 	spin_unlock(&GlobalMid_Lock);
 
-	rc = cifs_sign_smb2(iov, nvec, server, &mid->sequence_number);
-	if (rc) {
-		mutex_unlock(&server->srv_mutex);
-		goto out_err;
-	}
-
-	mid->receive = receive;
-	mid->callback = callback;
-	mid->callback_data = cbdata;
-	mid->midState = MID_REQUEST_SUBMITTED;
 
 	cifs_in_send_inc(server);
-	rc = smb_sendv(server, iov, nvec);
+	rc = smb_send_rqst(server, rqst);
 	cifs_in_send_dec(server);
 	cifs_save_when_sent(mid);
+
+	if (rc < 0)
+		server->sequence_number -= 2;
 	mutex_unlock(&server->srv_mutex);
 
-	if (rc)
-		goto out_err;
+	if (rc == 0)
+		return 0;
 
-	return rc;
-out_err:
-	delete_mid(mid);
-	atomic_dec(&server->inFlight);
+	cifs_delete_mid(mid);
+	add_credits(server, 1, optype);
 	wake_up(&server->request_q);
 	return rc;
 }
@@ -408,17 +588,17 @@ out_err:
  */
 int
 SendReceiveNoRsp(const unsigned int xid, struct cifs_ses *ses,
-		struct smb_hdr *in_buf, int flags)
+		 char *in_buf, int flags)
 {
 	int rc;
 	struct kvec iov[1];
 	int resp_buf_type;
 
-	iov[0].iov_base = (char *)in_buf;
-	iov[0].iov_len = be32_to_cpu(in_buf->smb_buf_length) + 4;
+	iov[0].iov_base = in_buf;
+	iov[0].iov_len = get_rfc1002_length(in_buf) + 4;
 	flags |= CIFS_NO_RESP;
 	rc = SendReceive2(xid, ses, iov, 1, &resp_buf_type, flags);
-	cFYI(DBG2, "SendRcvNoRsp flags %d rc %d", flags, rc);
+	cifs_dbg(NOISY, "SendRcvNoRsp flags %d rc %d\n", flags, rc);
 
 	return rc;
 }
@@ -428,11 +608,11 @@ cifs_sync_mid_result(struct mid_q_entry *mid, struct TCP_Server_Info *server)
 {
 	int rc = 0;
 
-	cFYI(1, "%s: cmd=%d mid=%d state=%d", __func__, mid->command,
-		mid->mid, mid->midState);
+	cifs_dbg(FYI, "%s: cmd=%d mid=%llu state=%d\n",
+		 __func__, le16_to_cpu(mid->command), mid->mid, mid->mid_state);
 
 	spin_lock(&GlobalMid_Lock);
-	switch (mid->midState) {
+	switch (mid->mid_state) {
 	case MID_RESPONSE_RECEIVED:
 		spin_unlock(&GlobalMid_Lock);
 		return rc;
@@ -447,8 +627,8 @@ cifs_sync_mid_result(struct mid_q_entry *mid, struct TCP_Server_Info *server)
 		break;
 	default:
 		list_del_init(&mid->qhead);
-		cERROR(1, "%s: invalid mid state mid=%d state=%d", __func__,
-			mid->mid, mid->midState);
+		cifs_dbg(VFS, "%s: invalid mid state mid=%llu state=%d\n",
+			 __func__, mid->mid, mid->mid_state);
 		rc = -EIO;
 	}
 	spin_unlock(&GlobalMid_Lock);
@@ -457,188 +637,185 @@ cifs_sync_mid_result(struct mid_q_entry *mid, struct TCP_Server_Info *server)
 	return rc;
 }
 
-/*
- * An NT cancel request header looks just like the original request except:
- *
- * The Command is SMB_COM_NT_CANCEL
- * The WordCount is zeroed out
- * The ByteCount is zeroed out
- *
- * This function mangles an existing request buffer into a
- * SMB_COM_NT_CANCEL request and then sends it.
- */
-static int
-send_nt_cancel(struct TCP_Server_Info *server, struct smb_hdr *in_buf,
-		struct mid_q_entry *mid)
+static inline int
+send_cancel(struct TCP_Server_Info *server, void *buf, struct mid_q_entry *mid)
 {
-	int rc = 0;
-
-	/* -4 for RFC1001 length and +2 for BCC field */
-	in_buf->smb_buf_length = cpu_to_be32(sizeof(struct smb_hdr) - 4  + 2);
-	in_buf->Command = SMB_COM_NT_CANCEL;
-	in_buf->WordCount = 0;
-	put_bcc(0, in_buf);
-
-	mutex_lock(&server->srv_mutex);
-	rc = cifs_sign_smb(in_buf, server, &mid->sequence_number);
-	if (rc) {
-		mutex_unlock(&server->srv_mutex);
-		return rc;
-	}
-	rc = smb_send(server, in_buf, be32_to_cpu(in_buf->smb_buf_length));
-	mutex_unlock(&server->srv_mutex);
-
-	cFYI(1, "issued NT_CANCEL for mid %u, rc = %d",
-		in_buf->Mid, rc);
-
-	return rc;
+	return server->ops->send_cancel ?
+				server->ops->send_cancel(server, buf, mid) : 0;
 }
 
 int
 cifs_check_receive(struct mid_q_entry *mid, struct TCP_Server_Info *server,
 		   bool log_error)
 {
-	unsigned int len = be32_to_cpu(mid->resp_buf->smb_buf_length) + 4;
+	unsigned int len = get_rfc1002_length(mid->resp_buf) + 4;
 
 	dump_smb(mid->resp_buf, min_t(u32, 92, len));
 
 	/* convert the length into a more usable form */
-	if (server->sec_mode & (SECMODE_SIGN_REQUIRED | SECMODE_SIGN_ENABLED)) {
+	if (server->sign) {
 		struct kvec iov;
+		int rc = 0;
+		struct smb_rqst rqst = { .rq_iov = &iov,
+					 .rq_nvec = 1 };
 
 		iov.iov_base = mid->resp_buf;
 		iov.iov_len = len;
 		/* FIXME: add code to kill session */
-		if (cifs_verify_signature(&iov, 1, server,
-					  mid->sequence_number + 1) != 0)
-			cERROR(1, "Unexpected SMB signature");
+		rc = cifs_verify_signature(&rqst, server,
+					   mid->sequence_number);
+		if (rc)
+			cifs_dbg(VFS, "SMB signature verification returned error = %d\n",
+				 rc);
 	}
 
 	/* BB special case reconnect tid and uid here? */
 	return map_smb_to_linux_error(mid->resp_buf, log_error);
 }
 
+struct mid_q_entry *
+cifs_setup_request(struct cifs_ses *ses, struct smb_rqst *rqst)
+{
+	int rc;
+	struct smb_hdr *hdr = (struct smb_hdr *)rqst->rq_iov[0].iov_base;
+	struct mid_q_entry *mid;
+
+	rc = allocate_mid(ses, hdr, &mid);
+	if (rc)
+		return ERR_PTR(rc);
+	rc = cifs_sign_rqst(rqst, ses->server, &mid->sequence_number);
+	if (rc) {
+		cifs_delete_mid(mid);
+		return ERR_PTR(rc);
+	}
+	return mid;
+}
+
 int
 SendReceive2(const unsigned int xid, struct cifs_ses *ses,
-	     struct kvec *iov, int n_vec, int *pRespBufType /* ret */,
+	     struct kvec *iov, int n_vec, int *resp_buf_type /* ret */,
 	     const int flags)
 {
 	int rc = 0;
-	int long_op;
+	int timeout, optype;
 	struct mid_q_entry *midQ;
-	struct smb_hdr *in_buf = iov[0].iov_base;
+	char *buf = iov[0].iov_base;
+	unsigned int credits = 1;
+	struct smb_rqst rqst = { .rq_iov = iov,
+				 .rq_nvec = n_vec };
 
-	long_op = flags & CIFS_TIMEOUT_MASK;
+	timeout = flags & CIFS_TIMEOUT_MASK;
+	optype = flags & CIFS_OP_MASK;
 
-	*pRespBufType = CIFS_NO_BUFFER;  /* no response buf yet */
+	*resp_buf_type = CIFS_NO_BUFFER;  /* no response buf yet */
 
 	if ((ses == NULL) || (ses->server == NULL)) {
-		cifs_small_buf_release(in_buf);
-		cERROR(1, "Null session");
+		cifs_small_buf_release(buf);
+		cifs_dbg(VFS, "Null session\n");
 		return -EIO;
 	}
 
 	if (ses->server->tcpStatus == CifsExiting) {
-		cifs_small_buf_release(in_buf);
+		cifs_small_buf_release(buf);
 		return -ENOENT;
 	}
 
-	/* Ensure that we do not send more than 50 overlapping requests
-	   to the same server. We may make this configurable later or
-	   use ses->maxReq */
+	/*
+	 * Ensure that we do not send more than 50 overlapping requests
+	 * to the same server. We may make this configurable later or
+	 * use ses->maxReq.
+	 */
 
-	rc = wait_for_free_request(ses->server, long_op);
+	rc = wait_for_free_request(ses->server, timeout, optype);
 	if (rc) {
-		cifs_small_buf_release(in_buf);
+		cifs_small_buf_release(buf);
 		return rc;
 	}
 
-	/* make sure that we sign in the same order that we send on this socket
-	   and avoid races inside tcp sendmsg code that could cause corruption
-	   of smb data */
+	/*
+	 * Make sure that we sign in the same order that we send on this socket
+	 * and avoid races inside tcp sendmsg code that could cause corruption
+	 * of smb data.
+	 */
 
 	mutex_lock(&ses->server->srv_mutex);
 
-	rc = allocate_mid(ses, in_buf, &midQ);
-	if (rc) {
+	midQ = ses->server->ops->setup_request(ses, &rqst);
+	if (IS_ERR(midQ)) {
 		mutex_unlock(&ses->server->srv_mutex);
-		cifs_small_buf_release(in_buf);
+		cifs_small_buf_release(buf);
 		/* Update # of requests on wire to server */
-		atomic_dec(&ses->server->inFlight);
-		wake_up(&ses->server->request_q);
-		return rc;
-	}
-	rc = cifs_sign_smb2(iov, n_vec, ses->server, &midQ->sequence_number);
-	if (rc) {
-		mutex_unlock(&ses->server->srv_mutex);
-		cifs_small_buf_release(in_buf);
-		goto out;
+		add_credits(ses->server, 1, optype);
+		return PTR_ERR(midQ);
 	}
 
-	midQ->midState = MID_REQUEST_SUBMITTED;
+	midQ->mid_state = MID_REQUEST_SUBMITTED;
 	cifs_in_send_inc(ses->server);
 	rc = smb_sendv(ses->server, iov, n_vec);
 	cifs_in_send_dec(ses->server);
 	cifs_save_when_sent(midQ);
 
+	if (rc < 0)
+		ses->server->sequence_number -= 2;
 	mutex_unlock(&ses->server->srv_mutex);
 
 	if (rc < 0) {
-		cifs_small_buf_release(in_buf);
+		cifs_small_buf_release(buf);
 		goto out;
 	}
 
-	if (long_op == CIFS_ASYNC_OP) {
-		cifs_small_buf_release(in_buf);
+	if (timeout == CIFS_ASYNC_OP) {
+		cifs_small_buf_release(buf);
 		goto out;
 	}
 
 	rc = wait_for_response(ses->server, midQ);
 	if (rc != 0) {
-		send_nt_cancel(ses->server, in_buf, midQ);
+		send_cancel(ses->server, buf, midQ);
 		spin_lock(&GlobalMid_Lock);
-		if (midQ->midState == MID_REQUEST_SUBMITTED) {
+		if (midQ->mid_state == MID_REQUEST_SUBMITTED) {
 			midQ->callback = DeleteMidQEntry;
 			spin_unlock(&GlobalMid_Lock);
-			cifs_small_buf_release(in_buf);
-			atomic_dec(&ses->server->inFlight);
-			wake_up(&ses->server->request_q);
+			cifs_small_buf_release(buf);
+			add_credits(ses->server, 1, optype);
 			return rc;
 		}
 		spin_unlock(&GlobalMid_Lock);
 	}
 
-	cifs_small_buf_release(in_buf);
+	cifs_small_buf_release(buf);
 
 	rc = cifs_sync_mid_result(midQ, ses->server);
 	if (rc != 0) {
-		atomic_dec(&ses->server->inFlight);
-		wake_up(&ses->server->request_q);
+		add_credits(ses->server, 1, optype);
 		return rc;
 	}
 
-	if (!midQ->resp_buf || midQ->midState != MID_RESPONSE_RECEIVED) {
+	if (!midQ->resp_buf || midQ->mid_state != MID_RESPONSE_RECEIVED) {
 		rc = -EIO;
-		cFYI(1, "Bad MID state?");
+		cifs_dbg(FYI, "Bad MID state?\n");
 		goto out;
 	}
 
-	iov[0].iov_base = (char *)midQ->resp_buf;
-	iov[0].iov_len = be32_to_cpu(midQ->resp_buf->smb_buf_length) + 4;
-	if (midQ->largeBuf)
-		*pRespBufType = CIFS_LARGE_BUFFER;
+	buf = (char *)midQ->resp_buf;
+	iov[0].iov_base = buf;
+	iov[0].iov_len = get_rfc1002_length(buf) + 4;
+	if (midQ->large_buf)
+		*resp_buf_type = CIFS_LARGE_BUFFER;
 	else
-		*pRespBufType = CIFS_SMALL_BUFFER;
+		*resp_buf_type = CIFS_SMALL_BUFFER;
 
-	rc = cifs_check_receive(midQ, ses->server, flags & CIFS_LOG_ERROR);
+	credits = ses->server->ops->get_credits(midQ);
 
-	/* mark it so buf will not be freed by delete_mid */
+	rc = ses->server->ops->check_receive(midQ, ses->server,
+					     flags & CIFS_LOG_ERROR);
+
+	/* mark it so buf will not be freed by cifs_delete_mid */
 	if ((flags & CIFS_NO_RESP) == 0)
 		midQ->resp_buf = NULL;
 out:
-	delete_mid(midQ);
-	atomic_dec(&ses->server->inFlight);
-	wake_up(&ses->server->request_q);
+	cifs_delete_mid(midQ);
+	add_credits(ses->server, credits, optype);
 
 	return rc;
 }
@@ -646,17 +823,17 @@ out:
 int
 SendReceive(const unsigned int xid, struct cifs_ses *ses,
 	    struct smb_hdr *in_buf, struct smb_hdr *out_buf,
-	    int *pbytes_returned, const int long_op)
+	    int *pbytes_returned, const int timeout)
 {
 	int rc = 0;
 	struct mid_q_entry *midQ;
 
 	if (ses == NULL) {
-		cERROR(1, "Null smb session");
+		cifs_dbg(VFS, "Null smb session\n");
 		return -EIO;
 	}
 	if (ses->server == NULL) {
-		cERROR(1, "Null tcp session");
+		cifs_dbg(VFS, "Null tcp session\n");
 		return -EIO;
 	}
 
@@ -669,12 +846,12 @@ SendReceive(const unsigned int xid, struct cifs_ses *ses,
 
 	if (be32_to_cpu(in_buf->smb_buf_length) > CIFSMaxBufSize +
 			MAX_CIFS_HDR_SIZE - 4) {
-		cERROR(1, "Illegal length, greater than maximum frame, %d",
-			   be32_to_cpu(in_buf->smb_buf_length));
+		cifs_dbg(VFS, "Illegal length, greater than maximum frame, %d\n",
+			 be32_to_cpu(in_buf->smb_buf_length));
 		return -EIO;
 	}
 
-	rc = wait_for_free_request(ses->server, long_op);
+	rc = wait_for_free_request(ses->server, timeout, 0);
 	if (rc)
 		return rc;
 
@@ -688,8 +865,7 @@ SendReceive(const unsigned int xid, struct cifs_ses *ses,
 	if (rc) {
 		mutex_unlock(&ses->server->srv_mutex);
 		/* Update # of requests on wire to server */
-		atomic_dec(&ses->server->inFlight);
-		wake_up(&ses->server->request_q);
+		add_credits(ses->server, 1, 0);
 		return rc;
 	}
 
@@ -699,30 +875,33 @@ SendReceive(const unsigned int xid, struct cifs_ses *ses,
 		goto out;
 	}
 
-	midQ->midState = MID_REQUEST_SUBMITTED;
+	midQ->mid_state = MID_REQUEST_SUBMITTED;
 
 	cifs_in_send_inc(ses->server);
 	rc = smb_send(ses->server, in_buf, be32_to_cpu(in_buf->smb_buf_length));
 	cifs_in_send_dec(ses->server);
 	cifs_save_when_sent(midQ);
+
+	if (rc < 0)
+		ses->server->sequence_number -= 2;
+
 	mutex_unlock(&ses->server->srv_mutex);
 
 	if (rc < 0)
 		goto out;
 
-	if (long_op == CIFS_ASYNC_OP)
+	if (timeout == CIFS_ASYNC_OP)
 		goto out;
 
 	rc = wait_for_response(ses->server, midQ);
 	if (rc != 0) {
-		send_nt_cancel(ses->server, in_buf, midQ);
+		send_cancel(ses->server, in_buf, midQ);
 		spin_lock(&GlobalMid_Lock);
-		if (midQ->midState == MID_REQUEST_SUBMITTED) {
+		if (midQ->mid_state == MID_REQUEST_SUBMITTED) {
 			/* no longer considered to be "in-flight" */
 			midQ->callback = DeleteMidQEntry;
 			spin_unlock(&GlobalMid_Lock);
-			atomic_dec(&ses->server->inFlight);
-			wake_up(&ses->server->request_q);
+			add_credits(ses->server, 1, 0);
 			return rc;
 		}
 		spin_unlock(&GlobalMid_Lock);
@@ -730,25 +909,23 @@ SendReceive(const unsigned int xid, struct cifs_ses *ses,
 
 	rc = cifs_sync_mid_result(midQ, ses->server);
 	if (rc != 0) {
-		atomic_dec(&ses->server->inFlight);
-		wake_up(&ses->server->request_q);
+		add_credits(ses->server, 1, 0);
 		return rc;
 	}
 
 	if (!midQ->resp_buf || !out_buf ||
-	    midQ->midState != MID_RESPONSE_RECEIVED) {
+	    midQ->mid_state != MID_RESPONSE_RECEIVED) {
 		rc = -EIO;
-		cERROR(1, "Bad MID state?");
+		cifs_dbg(VFS, "Bad MID state?\n");
 		goto out;
 	}
 
-	*pbytes_returned = be32_to_cpu(midQ->resp_buf->smb_buf_length);
+	*pbytes_returned = get_rfc1002_length(midQ->resp_buf);
 	memcpy(out_buf, midQ->resp_buf, *pbytes_returned + 4);
 	rc = cifs_check_receive(midQ, ses->server, 0);
 out:
-	delete_mid(midQ);
-	atomic_dec(&ses->server->inFlight);
-	wake_up(&ses->server->request_q);
+	cifs_delete_mid(midQ);
+	add_credits(ses->server, 1, 0);
 
 	return rc;
 }
@@ -772,7 +949,7 @@ send_lock_cancel(const unsigned int xid, struct cifs_tcon *tcon,
 
 	pSMB->LockType = LOCKING_ANDX_CANCEL_LOCK|LOCKING_ANDX_LARGE_FILES;
 	pSMB->Timeout = 0;
-	pSMB->hdr.Mid = GetNextMid(ses->server);
+	pSMB->hdr.Mid = get_next_mid(ses->server);
 
 	return SendReceive(xid, ses, in_buf, out_buf,
 			&bytes_returned, 0);
@@ -789,13 +966,13 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifs_tcon *tcon,
 	struct cifs_ses *ses;
 
 	if (tcon == NULL || tcon->ses == NULL) {
-		cERROR(1, "Null smb session");
+		cifs_dbg(VFS, "Null smb session\n");
 		return -EIO;
 	}
 	ses = tcon->ses;
 
 	if (ses->server == NULL) {
-		cERROR(1, "Null tcp session");
+		cifs_dbg(VFS, "Null tcp session\n");
 		return -EIO;
 	}
 
@@ -808,12 +985,12 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifs_tcon *tcon,
 
 	if (be32_to_cpu(in_buf->smb_buf_length) > CIFSMaxBufSize +
 			MAX_CIFS_HDR_SIZE - 4) {
-		cERROR(1, "Illegal length, greater than maximum frame, %d",
-			   be32_to_cpu(in_buf->smb_buf_length));
+		cifs_dbg(VFS, "Illegal length, greater than maximum frame, %d\n",
+			 be32_to_cpu(in_buf->smb_buf_length));
 		return -EIO;
 	}
 
-	rc = wait_for_free_request(ses->server, CIFS_BLOCKING_OP);
+	rc = wait_for_free_request(ses->server, CIFS_BLOCKING_OP, 0);
 	if (rc)
 		return rc;
 
@@ -831,41 +1008,45 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifs_tcon *tcon,
 
 	rc = cifs_sign_smb(in_buf, ses->server, &midQ->sequence_number);
 	if (rc) {
-		delete_mid(midQ);
+		cifs_delete_mid(midQ);
 		mutex_unlock(&ses->server->srv_mutex);
 		return rc;
 	}
 
-	midQ->midState = MID_REQUEST_SUBMITTED;
+	midQ->mid_state = MID_REQUEST_SUBMITTED;
 	cifs_in_send_inc(ses->server);
 	rc = smb_send(ses->server, in_buf, be32_to_cpu(in_buf->smb_buf_length));
 	cifs_in_send_dec(ses->server);
 	cifs_save_when_sent(midQ);
+
+	if (rc < 0)
+		ses->server->sequence_number -= 2;
+
 	mutex_unlock(&ses->server->srv_mutex);
 
 	if (rc < 0) {
-		delete_mid(midQ);
+		cifs_delete_mid(midQ);
 		return rc;
 	}
 
 	/* Wait for a reply - allow signals to interrupt. */
 	rc = wait_event_interruptible(ses->server->response_q,
-		(!(midQ->midState == MID_REQUEST_SUBMITTED)) ||
+		(!(midQ->mid_state == MID_REQUEST_SUBMITTED)) ||
 		((ses->server->tcpStatus != CifsGood) &&
 		 (ses->server->tcpStatus != CifsNew)));
 
 	/* Were we interrupted by a signal ? */
 	if ((rc == -ERESTARTSYS) &&
-		(midQ->midState == MID_REQUEST_SUBMITTED) &&
+		(midQ->mid_state == MID_REQUEST_SUBMITTED) &&
 		((ses->server->tcpStatus == CifsGood) ||
 		 (ses->server->tcpStatus == CifsNew))) {
 
 		if (in_buf->Command == SMB_COM_TRANSACTION2) {
 			/* POSIX lock. We send a NT_CANCEL SMB to cause the
 			   blocking lock to return. */
-			rc = send_nt_cancel(ses->server, in_buf, midQ);
+			rc = send_cancel(ses->server, in_buf, midQ);
 			if (rc) {
-				delete_mid(midQ);
+				cifs_delete_mid(midQ);
 				return rc;
 			}
 		} else {
@@ -877,16 +1058,16 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifs_tcon *tcon,
 			/* If we get -ENOLCK back the lock may have
 			   already been removed. Don't exit in this case. */
 			if (rc && rc != -ENOLCK) {
-				delete_mid(midQ);
+				cifs_delete_mid(midQ);
 				return rc;
 			}
 		}
 
 		rc = wait_for_response(ses->server, midQ);
 		if (rc) {
-			send_nt_cancel(ses->server, in_buf, midQ);
+			send_cancel(ses->server, in_buf, midQ);
 			spin_lock(&GlobalMid_Lock);
-			if (midQ->midState == MID_REQUEST_SUBMITTED) {
+			if (midQ->mid_state == MID_REQUEST_SUBMITTED) {
 				/* no longer considered to be "in-flight" */
 				midQ->callback = DeleteMidQEntry;
 				spin_unlock(&GlobalMid_Lock);
@@ -904,17 +1085,17 @@ SendReceiveBlockingLock(const unsigned int xid, struct cifs_tcon *tcon,
 		return rc;
 
 	/* rcvd frame is ok */
-	if (out_buf == NULL || midQ->midState != MID_RESPONSE_RECEIVED) {
+	if (out_buf == NULL || midQ->mid_state != MID_RESPONSE_RECEIVED) {
 		rc = -EIO;
-		cERROR(1, "Bad MID state?");
+		cifs_dbg(VFS, "Bad MID state?\n");
 		goto out;
 	}
 
-	*pbytes_returned = be32_to_cpu(midQ->resp_buf->smb_buf_length);
+	*pbytes_returned = get_rfc1002_length(midQ->resp_buf);
 	memcpy(out_buf, midQ->resp_buf, *pbytes_returned + 4);
 	rc = cifs_check_receive(midQ, ses->server, 0);
 out:
-	delete_mid(midQ);
+	cifs_delete_mid(midQ);
 	if (rstart && rc == -EACCES)
 		return -ERESTARTSYS;
 	return rc;